1.Field of the Invention
The present invention relates to a vacuum cleaner, and more particularly, to a filter device of a vacuum cleaner capable of self-removing dust attached to a filter in operation of a cleaner.
2.Description of the Background Art
In general, a vacuum cleaner is an electronic device for cleaning an indoor space such as a room, an office or the inside of a car and can remove undesired impurities such as dust existing at home or the inside of a car by using a suction force thereof.
FIG. 1 is a perspective view showing a structure of a general vacuum cleaner.
As shown therein, a general vacuum cleaner includes a cleaner main body 1 and a suction head 3 connected to the cleaner main body 1 by a suction hose 5 and an expansion pipe 4, for sucking dust and foreign substances from a floor.
The cleaner main body 1 includes a suction force generating part (not shown) for generating a suction force; and a filter device 6 for collecting dust and foreign substances by a suction force generated from the suction force generating part.
As shown in FIG. 2, the filter device is provided with a knob 8 and detachably attached to the inside of the cleaner main body 1. Thusly, a user can couple the filter device to the cleaner main body 1 or separate it therefrom by using the knob 8, more conveniently.
FIG. 3 is a disassembled perspective view showing a filter device of a conventional vacuum cleaner, and FIG. 4 is a longitudinal sectional view showing a filter device of a conventional vacuum cleaner.
The filter device 6 in accordance with the conventional art includes a casing 11 having a collecting space therein, a suction opening 14 through which air including dust is sucked and a discharge opening 15 through which purified air is discharged; and a filter 13 installed at the internal space of the casing 11, for filtering dust from air sucked through the suction opening 14.
The casing 11 is formed in a cylindrical shape an upper side of which is opened and includes a cover 12 installed for covering an upper surface of the casing 11; a filter supporter 18 positioned at the cover 12 and having a discharge opening 15 formed penetratingly, though which air purified by the filter 13 is discharged outside; a support wall body 16 protruded from an inner lower portion of the casing 11 at a predetermined height; and a pair of blocking plates 17 installed at an upper surface of the support wall body 17 to face each other so that relatively big dust or foreign substances of dust introduced into the casing 11 are prevented from escaping therefrom.
A process for collecting dust in the filter device of the conventional vacuum cleaner will now be described.
When power is applied, a suction force is generated from a suction force generating part (not shown), and dust and foreign substances sucked through the suction head 3 are sucked into the casing 11 through the suction opening 14 via the expansion pipe 4 and the suction hose 5. The dust sucked into the casing 11 is purified by the filter 1 and collected in the casing 11, and only the air purified while passing through the filter 13 is discharged through the discharge opening. Here, relatively heavy dust or foreign substances fall to a gap between the blocking plates 17 by their weights and are collected at the inner lower portion. The support wall body 16 prevents an eddy which may occur in the space under the blocking plate 17 to thereby prevent dust from floating again and being moved to a space above the blocking plate 17. Fine dust or foreign substances which are relatively light in weight are not collected in a space under the blocking plate 17 but float with air and are purified by the filter 13 again.
However, such a conventional vacuum cleaner has a problem in that the filter 13 has to be cleaned or replaced periodically. This is because when the vacuum cleaner is used for a certain period of time, fine dust is attached to the filter 13 of the filter device 6, thereby deteriorating a suction force. That is, since fine dust closes up a close mesh of the filter 13, it is difficult to discharge sucked air and finally a decrease in suction force is caused. Accordingly, if the filter 13 is not periodically cleaned or replaced, a cleaning operation is not performed actively due to the deterioration of the suction force.